TY - JOUR
T1 - Overexpression of the natural recO sequence and its effects on DNA repair of Escherichia coli
AU - Yang, Chi Ling
AU - Liu, Ying Hsu
AU - Wang, Tzu Chien V.
PY - 1996/1/2
Y1 - 1996/1/2
N2 - The recO gene is required for the RecF pathway of recombination and the repair of DNA daughter-strand gaps in Escherichia coli. In this work, the structural portion of recO was synthesized by the polymerase chain reaction (PCR) and cloned onto expression vectors at their Nco1 fusion cloning site, to eliminate the presence of mRNA leader sequence. While the plasmid carrying a P(tac) promoter failed to overproduce RecO, the plasmid carrying a T7∅10 promoter overproduced RecO in large quantity, indicating that the natural recO may be overexpressed. An increase of intracellular RecO, which may be due to the increased recO gene copies or to the induction of RecO synthesis, increased the UV resistance of recA, recF, and ssb cells, hut did not increase the UV resistance of uvrB, uvr-B recF, uvrB recA and uvrB ssb cells. We suggest that an increase of intracellular RecO may allow some recombination-deficient cells to perform more excision repair, thus increasing the survival. The possible causes for RecO overproduction on excision repair, and for the differential expression of recO by the P(tac) and T7 promoter plasmids are discussed.
AB - The recO gene is required for the RecF pathway of recombination and the repair of DNA daughter-strand gaps in Escherichia coli. In this work, the structural portion of recO was synthesized by the polymerase chain reaction (PCR) and cloned onto expression vectors at their Nco1 fusion cloning site, to eliminate the presence of mRNA leader sequence. While the plasmid carrying a P(tac) promoter failed to overproduce RecO, the plasmid carrying a T7∅10 promoter overproduced RecO in large quantity, indicating that the natural recO may be overexpressed. An increase of intracellular RecO, which may be due to the increased recO gene copies or to the induction of RecO synthesis, increased the UV resistance of recA, recF, and ssb cells, hut did not increase the UV resistance of uvrB, uvr-B recF, uvrB recA and uvrB ssb cells. We suggest that an increase of intracellular RecO may allow some recombination-deficient cells to perform more excision repair, thus increasing the survival. The possible causes for RecO overproduction on excision repair, and for the differential expression of recO by the P(tac) and T7 promoter plasmids are discussed.
KW - DNA repair
KW - E. coli
KW - RecO overproduction
KW - Recombination
UR - http://www.scopus.com/inward/record.url?scp=0030022656&partnerID=8YFLogxK
U2 - 10.1016/0921-8777(95)00027-5
DO - 10.1016/0921-8777(95)00027-5
M3 - 文章
C2 - 8538645
AN - SCOPUS:0030022656
SN - 0921-8777
VL - 362
SP - 21
EP - 28
JO - Mutation Research-DNA Repair
JF - Mutation Research-DNA Repair
IS - 1
ER -